ATi R420 will support DDR1, DDR 2 and then there’s GDDR3 memory, which could be used in future speed upgrades of the R4x0 family. The initial R420 will use DDR 2 memory which is finally stable and available, and can deliver over 1000MHz. The R300, R350 and consequently R360 also had support for DDR 1 and DDR 2 as R350 had its DDR II version following introduction of R350, Radeon 9800 PRO 128 MB DDR 1 few months earlier. The R420 will have 256 bit memory interface that can always be cut up to 128 bits if you need that. ATi R420 will support DDR1, DDR 2 and then there’s GDDR3 memory, which could be used in future speed upgrades of the R4x0 family. The initial R420 will use DDR 2 memory which is finally stable and available, and can deliver over 1000MHz. The R300, R350 and consequently R360 also had support for DDR 1 and DDR 2 as R350 had its DDR II version following introduction of R350, Radeon 9800 PRO 128 MB DDR 1 few months earlier. The R420 will have 256 bit memory interface that can always be cut up to 128 bits if you need that.